Turbine ring assembly with sealing

Abstract

A turbine ring assembly includes a ring support structure and a plurality of ring sectors made of CMC material and forming a turbine ring, each ring sector including an annular base with respective end portions having edges that are held facing an edge of the end portion of the annular base of a sector that is adjacent in the turbine ring. The assembly includes resilient holder devices for holding the ring sectors in position on the ring support structure, and each resilient holder device includes a spring element present beside the outside face of the ring support structure.

The invention claimed is: 
     
       1. A turbine ring assembly comprising a ring support structure and a plurality of ring sectors made of ceramic matrix composite material making up a turbine ring, each of the plurality of ring sectors comprising an annular base with, in a radial direction of the turbine ring, an inside face defining the inside face of the turbine ring and an outside face facing the inside face of the ring support structure, each said annular base including at each circumferential end a circumferential edge that is held facing a circumferential edge of the circumferential end of the annular base of an adjacent one of the plurality of ring sectors in the turbine ring, wherein the assembly comprises resilient holder devices, each of the resilient holder devices exerting a force on the circumferential ends of two adjacent ring sectors of the plurality of ring sectors, holding said two adjacent ring sectors of the plurality of ring sectors in position, and wherein each of the resilient holder devices comprises a spring element present beside the outside face of the ring support structure,
 wherein the turbine ring assembly comprises a plurality of gaskets, each of the plurality of gaskets extending axially over the circumferential ends of two adjacent ring sectors of the plurality of ring sectors at the facing edges of said ends, the resilient holder devices exerting force that holds each of the plurality of gaskets in contact with the circumferential ends of two adjacent ring sectors of the plurality of ring sectors, wherein the inside face of each of the plurality of ring sectors is coated with an abradable material layer. 
 
     
     
       2. The turbine ring assembly of  claim 1 , wherein:
 the ring support structure comprises an upstream annular radial flange and a downstream annular radial flange between which the plurality of ring sectors are held without being attached to said upstream annular radial and downstream annular radial flanges, each of the plurality of gaskets having an upstream end passing through a slot formed in the upstream radial flange and a downstream end passing through a slot formed in the downstream radial flange; 
 each of the plurality of ring sectors presents a K-shape in a plane defined by the radial direction and the circumferential direction of the turbine ring, with tabs extending from the outside face of the annular base over the circumferential ends of said annular base, circumferential edges of the tabs and the circumferential edges of the circumferential ends of each of the plurality of ring sectors being held respectively facing the circumferential edges of tabs and the circumferential edges of the plurality of ring sectors that are adjacent in the turbine ring; 
 each of the resilient holder devices exerts a force on the facing tabs of two adjacent ring sectors of the plurality of ring sectors that is directed radially towards the outside of the turbine ring, holding the corresponding gasket in contact with the circumferential ends of two adjacent ring sectors of the plurality of ring sectors. 
 
     
     
       3. The turbine ring assembly of  claim 2 , wherein the gaskets are constituted by strips of ceramic matrix composite material. 
     
     
       4. The turbine ring assembly of  claim 2 , wherein each of the resilient holder devices comprises a bolt and a spring, the bolt having a head present between the outside face of a gasket and the tabs of two adjacent ring sectors of the plurality of ring sectors, the spring being mounted in a prestressed state between a shroud of the ring support structure and a nut fastened to the end of the bolt remote from its end having the head. 
     
     
       5. The turbine ring assembly of  claim 1 , wherein:
 the ring support structure includes tabs that extend from the inside face of a shroud, each tab including a folded-over portion; 
 each ring sector includes tabs extending from the outside face of its annular base, each tab having a folded-over portion engaged with the folded-over portion of a tab of the ring structure; and 
 each of the resilient holder devices exerts a pressing force on each gasket of the plurality of gaskets holding the gasket in contact with the circumferential ends of two adjacent ring sectors. 
 
     
     
       6. The turbine ring assembly of  claim 5 , wherein each of the resilient holder devices comprises a shoe in contact with the top surface of the gasket, a rod extending vertically from the outside surface of the shoe, and a spring exerting a pressing force on the free end of the rod.